25 years ago – 1992
- Frost – On June 20, the temperature dropped to 25°F in many locations throughout Wisconsin. This caused injury to several tree species including: black ash, balsam fir, red pine, northern pin oak, and spruce in northwestern Wisconsin, and red pine and northern pin oak in Oneida and Vilas counties, north-central Wisconsin. Severe damage to new shoots of white spruce and balsam fir Christmas trees occurred in Taylor, Langlade, Oneida, Lincoln and Oconto counties. Injury to hardwoods often caused defoliation. Conifers affected by the frost had curled and crooked shoots that eventually died. In Vilas County, most of the injured red pine and oak did not reflush. In Eau Claire County, western Wisconsin, spruce, black walnut and several species of pine were injured. Seedling and sapling-size red pine were injured in Clark and Chippewa counties. Balsam fir, white spruce and white pine Christmas trees in northern Wisconsin were also injured by the early summer frost. Severe loss of new growth.
- White Grubs – Phyllophaga In Marinette County, (Section 16, T30N, R20E) high numbers of white grub larvae were observed in plantings of ash, maple, oak and walnut. These trees were being planted in alfalfa. In Portage county, (NWNW, Section 4, T21N, R7E) all larval stages were present at the time of planting red pine in sod on a 13 acre area. In Washburn County, heavy mortality occurred in a red pine planting due to white grub feeding. Heavy numbers of grubs were reported in new tree plantations in Door, Kewaunee and Manitowoc counties. The adult stage of white grubs, the May and June beetles, were observed in large numbers at night in urban areas in Oconto, Marinette and Marathon counties. Progeny of these beetles could produce heavy damage to nearby young tree plantings in the next two years.
50 years ago – 1967
- Pissodes approximatus Damage by this weevil was associated with red pine plantings on poor sites or frost pockets in the Northeast Area. The most severe infestations were found in Marinette, Oneida and Vilas counties during surveys for Scleroderris lagerbergii (Gremman).
- White-Pine Weevil, Pissodes strobi (Peck). Populations were generally low in all areas of the state. About 10% of the leaders were infested in a small white pine planting in Washburn County (Section 8, T41N, Rl3W). A few terminals of Norway spruce and Scotch pine Christmas trees were infested in Langlade and Oconto county plantations, and survival of weevils was poor in the east central counties. Heaviest infestations were reported from the West Central Area where 20% to 30% of the current leaders were infested in a few white pine plantations and averaged 10% to 15%. Although no white pine weevil control projects were conducted in the West Central Area this year, additional insecticide test plots were established on Black River State Forest plantations. Further investigation of a reported white pine weevil attack on red pine in Trempealeau County reported in 1966 (p. 7, Annual Report 1966) appears more likely to have been the work of Pissodes approximatus Hopkins. Large numbers of these weevils were found on stumps of red pine, cut for Christmas in the fall of 1966, when the site was re-examined in the spring of 1967. Older stumps showed evidence of previous attacks typical of P. approximatus. Evaluation of evidence available indicated that terminal attacks in 1966 occurred because breeding P. approximatus populations exceeded available stump areas and overflowed to the stems and terminals of living trees.
Content taken from the Forest Pest Conditions for Wisconsin Annual Reports from 1967 and 1992.